ddr: altera: sdram: Clean up sdram_calculate_size() part 1

Pluck out all of the CONFIG_HPS_SDR_CTRLCFG_* macros. This change
makes sdram.c completely clear of these macros and allows removing
of the ugly include of sdram.h . The namespace is now a much nicer
place!

Signed-off-by: Marek Vasut <marex@denx.de>